driver updates fail to install

[Matthew]

Two drivers fail to apply. Windows Update determines that
there are new versions of two drivers but installation
fails with access denied 0x80070005

The problem is possibly unrelated to the specifics of the
drivers, but the drivers are:
Microsoft Modem Driver Version 8.28.0.0
NVIDIA display software update released on July 28 2003

I have searched the web for hints on how to proceed. I
have tried:
renaming Windows\system32\CatRoot2
clearing WUTemp
clearing Windows\Temp (although some stuff remains
because it is in use it does not appear to be related by
name to the drivers involved)

Focusing in on the Microsoft Modem Driver, I have tried
renaming (also deleting) modem.sys and ltmdmnt.sys in
Windows\system32\drivers
Also, I have searched Windows for all references to
modem.sys and ltmdmnt.sys and deleted them from
everywhere except
Windows\Driver Cache\i386\driver.cab
Windows\Driver Cache\i386\sp1.cab

Of course, I have tried working on the drivers through
the system device manager:
uninstall, rollback, update, disable

What am I missing?
Any thoughts on how to proceed here?

 

[Jupiter Jones [MVP]]

Matthew;
Check with the manufacturers website and get the drivers directly from
them.

 

[Matthew]

I would have thought that Windows Update was the
authority for the Microsoft Modem Driver.

 

[Matthew]

Quite right though,
Going to Agere directly for the Lucent Win Modem driver
gets past it for the Microsoft Modem Driver (not
certified for XP though), and going directly to NVIDIA
for the ForceWare driver gets past it for the NVIDIA
display software (this appears to be certified for XP).

Thank you Jupiter Jones.

 

[Jupiter Jones [MVP]]

The drivers Microsoft has are from the manufacturer and they are
signed as well.
But they may not be the latest drivers as there is a lag for the
driver signing.